اثر پیش‌تیمار بذر با اسید سالیسیلیک و پلی آمین‌ها بر فعالیت بیوشیمیایی و فیزیولوژیکی گیاه بامیه تحت تنش دمای پایین

In order to investigate the effects of seed priming by plant growth regulators( salicylic acid, spermine and spermidine) on some physiological and biochemical characteristics of Okra (Abelmoschus esculentus CV Basenti) under low temperature stress a completely randomized design was conducted at 2014. Experimental treatments include priming of okra seeds with 0.1 mM concentration of Salicylic Acid, 0.5mM of spermine and spermidine 12 hours duration, and by distillated water and none-primed seeds. Seedling were kept in greenhouse untill then seedlings subjected to low temperature stress (8 ºC temperature for 270 minutes on four consecutive days) at six-leaf growth stage. After exposing the okra seedling to low temperature stress on, some physiological and biochemical parameters such as photosynthetic pigments, total carbohydrates, protein, proline, antioxidant enzyme activity, membrane integrity and chlorophyll content of leaves were measured. Result indicated that seed priming by salicylic acid and polyamines increased soluble carbohydrates vegetative, proline, antioxidant enzyme activity. Seed priming by salicylic acid and polyamines such as spermine and spermidine were enhanced memberane integrity via increase in soluble carbohydrates, proline content of leaves and antioxidant enzymes especialy catalas under low temperature stress. The greatest impact of seed priming for seedling growth under low temperature stress were obtained by priming of seeds by 0.1 mM concentration of Salicylic Acid.